User:Tilman Schirmer/Sandbox 212

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PleD activation

Activation via dimerization
Activation of PleD proceeds via phosphorylation-induced dimerization. Upon modification of Asp53 of the Rec domain, the intramolecular packing of the Rec and Rec' domains is changed. This in turn, reduces the Kd of dimerization considerably, because the dimerization interface of the (Rec-Rec')2 "stem" is improved. Stem mediated dimerization enhances diguanylate cyclase efficiency, because it favors formation of the catalytically competent (GGDEF)2 dimer (not shown here, but see back, bottom of page).

non-active state


monomer in solution, loose dimer in the crystal

activated state


Asp 53 modified by BeF3- to mimick phosphorylation, tight dimeric stem in the crystal